(Page 2 of discussion thread)

Hi Eve,

I've been enjoying reading the conversation between you and Claire, thank you! Please don't take it away to direct e-mails unless you really have to - you might be surprised how many people read the open exchanges, and benefit and learn as a result of it.

Just a quick one about pharmaceutical residues in urine:

1. You can read up about that here on the forum - please just check that you're not re-inventing the wheel. See here: forum.susana.org/component/kunena/175-ur...euse-or-infiltration
2. You also have pharmaceuticals in feces by the way, not just in urine.
3. In the scheme of things in developing countries, health risks from pharmaceutical residues in urine and ultimately on crops, is miniscule compared to all the other risks in sanitation provision (and due to lack of sanitation)
4. Soils are better in breaking down pharmaceutical residues in urine than aquatic environments which are receiving sewage. Therefore reuse of urine may be preferable from that perspective.

Also, somewhere above you talked about risks coming from urine infiltration. Don't forget also the risk of nitrate pollution of groundwater (although the health risks from that might also be smaller than previously thought, see here: forum.susana.org/component/kunena/193-gr...-health-implications (2 pages of discussion))

Regards,
Elisabeth

Hey Claire,

Thanks for your reply. Regarding your re-design, I haven't see any formal research, child adapted seats help children position better, but I honestly don't know if it helps the cross contamination, assume it would, it helps the child not fall into the hole! The squat plats with the sliding cover look like a good design because that covers totally the hole not in use. But again haven't seen any work. I guess the user's will have the best information - and being honest I'm not an experienced user!

If you had some separate models perhaps we could run some trials to see which factors ar most influential?

Yeah, the cholera is a key concern for you I guess, do you think your clients are in same areas as cholera hotspots?

My email is This email address is being protected from spambots. You need JavaScript enabled to view it. or Skype me eve.mackinnon be good to keep chatting about these questions

Lastly, on the pharmaceuticals - all the waste water engineering kids in my university study this- its a hot topic now for drinking water. Do you have any specific drugs - not my line but I could ask them...

Hi again! Thank you for sending me those papers! Do you know if there been any research into the relationship between toilet user interface design and risk of cross-contamination? We're currently in a redesign phase of our urinal, and it would be interesting to see what else is out there!

There's also very limited discussion around inactivation of pharmaceuticals in urine. Have you come across anything specific? I've also been fascinated recently about comparing the efficacy of various treatment technologies in degrading pharmaceuticals so let me know if you come across anything specific!

And your questions are very interesting! To date, there is neither anecdotal nor quantitative evidence of our users having cholera. We will be putting together a survey for our clients in early 2017, and we're planning to ask some public health questions -- and that would be an interesting one to include! We don't otherwise do specific public health surveillance.

However, we have done the following around public health awareness: provided regular health and toilet user/maintenance trainings to clients, sent out a series of text messages after the hurricane and flooding this year to inform users how to protect their homes and families, and distributed (very well-received!) hygiene kits that included soap and chlorox after the flooding. We do work with the government around public health e.g. we participate in health/WASH cluster conversations and co-host events like World Toilet Day.

Let me know if you have any more questions!

Hi Claire,

Yes it has excited me as well, this organic growth of a system.

Well I have been contacting their lively forum on Facebook and mainly the users dispose the waste themselves (considered the boat idea myself as a novel start up! any UK investors shout now!)

They compost it on top of their boats and the urine they dump either in the canal or in a drain.They use a variety of cover material and there is a lot of discussion on what composts better. Bearing in mind people who live on boats tend to already be committed to ecological and environmental sustainability so the toilet choice is a good fit. But they definitely like it from a convenience point of view and comfort.
All reported no related illnesses when I asked- but that was four respondents, and there must be far fewer infectious disease agents in their poo anyway.
The moderator who also sells the units did comment that people do not recognise it is a whole system (i.e. they must dispose of waste). But I am not sure what the fall back rate, is. There is few options on a boat and with the boat community growing because housing is SOOO expensive in London I can see this sanitation technology growing also.
The fact that people here manage their own waste does point to an improved and possibly more cost effective method and suggest that householders could collect their own waste to maybe organised transfer systems or disposal points, as people here do. The company would still have the waste and it would be allround a bit easier.

Another intriguing point is the fill time. The people on the boats refer to 2-3 months for emptying the solid... anecdotal of course..

For the urine risks, yeah, there is a bit but not much evidence now of urine collected from UDDT being pretty highly contaminated (see Bischel 2015 and Hoglund 2001)- I am sure this come from cross faecal contamination, it must as urine is pretty sterile and they cannot all have urinary tract infections which would be the only other cause. I saw this summer myself pretty high EC count in urine. So i am sure it is contaminated mostly.

But you know if it drains though soil probably ok right...

I am not sure how this would factor in Haiti with cholera risks. Did any of your clients ever have cholera and use the system> do you have a unique SOIL disease surveillance or follow the health updates from government etc?

Heaps of question too my end!

Hi Eve! Oh I'm so curious about CBS on canal boats! Where does their waste get dumped? Do they use dry cover material? Does the individual boat dump their own waste, or is their a collector boat that goes boat-to-boat? We had been joking during the flooding that maybe we would rent a kayak to do bucket collection, but maybe it's already a real thing!

SOIL does not collect urine. Here is a blog post that gives an overview of our current urine situation: www.oursoil.org/disinfecting-urine-and-being-claire-twa-1609/

When you consider the risks of urine, are you thinking directly of pathogens transmitted by urine? Or potential cross-contamination from feces?

Hi Claire,

For sure it's one of the biggest risks of latrines is that they flood (even sealed pit/raised pits) flood and especially in the respect of more extreme weather events - climate change - these factors should be totally factored into to considerations of choices of 'improved sanitation'. Although of course pit latrines will always have a place.

Not only that but they protect shallow ground water sources clearly much better than a pit latrine - although I think that urine disposed straight into the ground from CBS systems could be problematic under certain contexts (v.high density/shallow groundwater used for drinking water/or env.contamination).

Do you at SOIL collect urine?

One interesting aspect I'm looking at is the use of CBS on canal boats across central London. I haven't yet got figures but there are roughly 2000 live aboard canal boats and perhaps 10-20% are using CBS systems. What can we learn about user habits and emptying to support in other contexts?

Hey Eve! In response to your question, "are you thinking of water as a pathway from hand contamination (secondary) or from some escaped faecal matter from the container getting into shallow groundwater, or some other direct contamination of drinking water?" I was thinking more about direct contamination of drinking water, as well as fecal contamination of produce. (Mostly because those are the risks I consider personally!)

And here are a few more tangential (but maybe relevant!) thoughts:

• A few weeks ago there was a lot of flooding in Cap-Haitien, and it was a great argument for container-based sanitation for flood-prone areas as containers can be sealed and removed from rising water (which is definitely not the case for latrines!). Since the flooding, there have been more reported cases of cholera.
• Re: your question about hand washing, I only recently learned that it's a lot more complicated than I realized! Specifically that effective drying is essential!
• For the risks associated with aerosol particles, has there been any sort of comparison between dry/non-flushing toilets and wet/flushing toilets?

Dear Claire, Thanks so much for your feedback on the exposure indicators I was thinking about and bringing your field knowledge to the table! Its really helpful! My responses which I wanted to share with you are in red.

2. 2. Which of the risk factors is of highest importance in terms of risk to human health? 
a. #1: Prevalence rate of diarrheal disease mortality/morbidity

I agree I fully see the prevalence rate in communities as a key risk factors in terms of the consequences of exposure. Also the disease agent is important.

3. Which is the least important risk factor in each of the components?
a. Hazard Intensity Risk Factors: Incidence rate of infectious outbreaks.
b. Hazardous Events Risk Factors: Availability of anal cleansing materials.
c. Exposure Pathways Risk Factors: Flooring type.
d. Vulnerability Risk Factors: Age of user/immunity or health status of operator.

4. How well do indicators correlate with risk factors and quantify the level of risk in appropriate terms? 

It’s good!

5. Are there any indicators you would change?
a. I would change “Inadequate separation of toilets from living areas.” Using distance as a measurement of separation between food preparation are and toilet seems arbitrary. Also, if toilet design ensures containment of feces/urine, how much does it matter where the toilet is located?

It seems reasonable to say that if waste is totally contained the location of the toilet does not matter.
Of course it’s the benefit of CBS it can go anywhere.

The risk would increase with an increase in likelihood of spillages/un-containment and that risk maybe higher if it occurred next to people than further away from living area.

b. I’d also change “availability of anal cleansing materials” to “disposal of anal cleansing materials.”
c. Proportion of people trained in last 6 months: Training is important, but the impact is not number of people trained, but the number of people who leave the training viewing diarrheal disease as a severe health impact AND understanding how to minimize risks to themselves and their communities.

I fully agree here is that the attitude is the most important aspect for prevention of accident/exposure risk.

I can only think of conducting an attitude survey as a way to measure this, but I guess the assumption being that training increases safety awareness/attitudes normally.

6. How useful would you find this exercise is assessing exposure in your organisation? 

It’s very useful! It already has encouraged thought around appropriate PPE for staff as well as what should be discussed with CBS clients regarding minimum hygiene standards.

That’s’ great!
It would be really great attempt to quantify the risk and understand how you already manage the risks and how this is contributing to the risk level overall.

It sounds like this discussion and awareness raising is an important aspect to reduce risks.

7. Do you think the list of factors and indicators is too LONG or too SHORT? 

It could be more in-depth regarding exposure pathways for operators e.g. based on the various steps and activities of the container-based sanitation, what are the specific risks?

Yes I agree… This list of indicators is not suitable to really assess the risk level on site. A risk assessment should identify likely transmission routes. .

8. Any other comments?

I think that there could be more conversation about factors like water and food habits. There’s also a lot of focus on individual behavior, but not enough on community behavior. E.g. I can contract diarrhea if my neighbor doesn’t wash their hands.

I have purposefully avoided food/water – I guess I was trying to keep it simple! Trying to only look at risks directly related to the use of the CBS toilet. Food I have considered a secondary pathway and have included in models.

I did not consider water as a pathway, mainly to try and simplify the exposure routes, but this could be considered, I guess all contexts will be different and the assessment must be able to identify the specific pathways.

Just a question: are you thinking of water as a pathway from hand contamination (secondary) or from some escaped faecal matter from the container getting into shallow groundwater, or some other direct contamination of drinking water?

Dear Elisabeth, Anna,

Thanks so much for your feedback!

Elisabeth, the exposure factors for CBS are discussed from a theoretical perspective mainly, based on literature review of common pathways and risk factors for diarrheal transmission.

Fully agree on making it more operational - I propose a list of key risk factors and indicators for each aspect of exposure and from that have a sort of composite index for the system. It might be used as a predictive index or to gauge the parts of a system that are most prone to exposure.

- A more operational risk assessment tool I have been looking at this summer is adapting the SSP frameworks- I conducted an exploratory study this summer with support from an CBS organisation in Kenya. Hopefully this baseline activity will lead to a fully operational risk assessment tool tat CBS organisations have a hand in developing.

- Sanipath is an interesting model for quantitative and qualitative aspects of exposure pathway. The bayesian modelling techniques and resulting exposure probabilities depends slightly on arbitrary behaviour frequencies, that are interesting, but to my mind also a little conceptual for appropriate to use in real life risk assessments. As far as I am aware it does not pinpoint, where exposure occurs, which is also very valuable.

- I have used instead a more probabilistic risk assessment methodology; expert guidance of a team in the field or with knowledge of expected frequencies from records. I am not sure whether this is better, the hope is to develop this in 2017 and develop an appropriate yet- simple methodology.

That being said, Sanipath is really a great method for broader WASH assessments.

Anna - i will respond on your comments later!!! Thanks so much for engaging!!

Eve

Hi Eve,

Thanks for posting this. Good to see that you already got one response from Claire at SOIL, Haiti.

The document that you had attached was a bit heavy with 17 MB. Keeping in mind people with slower internet connection, I suggest you also add it as a pdf file.

And here is the Figure 1 that you mentioned:




I couldn't quite figure out how you get from this rather theoretical exercise to something tangible for organizations doing container-based sanitation? Could you give some examples of how you see this used in practice?

Also, have you thought about linking your research up with the SaniPath work - there seems to be some similar interests? See here on the forum about SaniPath:

forum.susana.org/forum/categories/26-hea...emory-university-usa

Regards,
Elisabeth

Hi Eve! This is really cool! I work as a Program Advisor with SOIL in Haiti, and here are my responses to your questions.

Key questions for the container based system managers, researchers and interested parties:

1. How would you rank the categories of exposure in terms of exposure related risk to human health?
Hazard Intensity: 4
b. Hazardous Events: 1
c. Exposure Pathways: 2
d. Receptor Vulnerability: 4

2. 2. Which of the risk factors is of highest importance in terms of risk to human health?
a. #1: Prevalence rate of diarrheal disease mortality/morbidity

3. Which is the least important risk factor in each of the components?
a. Hazard Intensity Risk Factors: Incidence rate of infectious outbreaks.
b. Hazardous Events Risk Factors: Availability of anal cleansing materials.
c. Exposure Pathways Risk Factors: Flooring type.
d. Vulnerability Risk Factors: Age of user/immunity or health status of operator.

4. How well do indicators correlate with risk factors and quantify the level of risk in appropriate terms?

It’s good!

5. Are there any indicators you would change?
a. I would change “Inadequate separation of toilets from living areas.” Using distance as a measurement of separation between food preparation are and toilet seems arbitrary. Also, if toilet design ensures containment of feces/urine, how much does it matter where the toilet is located?
b. I’d also change “availability of anal cleansing materials” to “disposal of anal cleansing materials.”
c. Proportion of people trained in last 6 months: Training is important, but the impact is not number of people trained, but the number of people who leave the training viewing diarrheal disease as a severe health impact AND understanding how to minimize risks to themselves and their communities.

6. How useful would you find this exercise is assessing exposure in your organisation?

It’s very useful! It already has encouraged thought around appropriate PPE for staff as well as what should be discussed with CBS clients regarding minimum hygiene standards.

7. Do you think the list of factors and indicators is too LONG or too SHORT?

It could be more in-depth regarding exposure pathways for operators e.g. based on the various steps and activities of the container-based sanitation, what are the specific risks?

8. Any other comments?

I think that there could be more conversation about factors like water and food habits. There’s also a lot of focus on individual behavior, but not enough on community behavior. E.g. I can contract diarrhea if my neighbor doesn’t wash their hands.

Hello all, I’m developing a suite of useful indicators for exposure risk factors in CBS.

The outcome of this is a proposed set of indicators that aligns the concept of exposure across a range of social, environmental, biological, regulatory and behavioural risk factors in each category and compares risk across systems.

The risk framework would complement semi-quantitative risk ranking and prioritisation and quantitative studies measuring concentrations of faecal indicator bacteria on exposure routes, and qualitative studies to understand vulnerable populations and exposure groups. This work will also validate the risk factors included in this metric. The framework is expected to help private organisation, public institutions and regulators monitor and assess key risks.

So I am asking the community their VIEWS and RESPONSES on the risk factors attached in the documents.
Briefly a conceptual exposure model is shown in figure 1:

There are 4 categories of exposure: 1) Hazard – 2) Hazardous Events – 3) Exposure Routes – 4) Receptor

--- 11 risk factors based on literature review and observation of container based systems in a pre-test case study development environment.




Each risk factor has a sub-set of risk indicators which are given a numerical score of risk (based 1-3) to arrive at a total risk score for the system component (each aspect of the CBS can be assessed individually i.e. user interface, collection and conveyance and waste transfer, and according to user, operator or community exposure groups).

---- 20 Key Risk Indicators (KRI) are proposed to measure the exposure within the system.
Using the spread sheet attached to understand the relevant definitions the communities’ feedback on the questions below would be super helpful in validating the risk factors.


Key questions for the container based system managers, researchers and interested parties:

1. How would you rank the categories of exposure in terms of exposure related risk to human health?
(Hazard Intensity, Hazardous Events, Exposure Pathways and Receptor Vulnerability) (1 being lowest -4 being highest or equal)

2. Which of the risk factors is of highest importance in terms of risk to human health?

3. Which is the least important risk factor in each of the components?

4. How well do indicators correlate with risk factors and quantify the level of risk in appropriate terms?

5. Are there any indicators you would change?

5. How useful would you find this exercise is assessing exposure in your organisation?

6. Do you think the list of factors and indicators is too LONG or too SHORT?

7. Any other comments?